Volkswagen Polo Quiz
Refrrigerant R134a Servicing

Flushing Not Necessary

In this manual: Refrrigerant R134a Servicing
General Paint Information — 128Towing Guide — 10Whels, Tires, Whel Alignment — 126Battery, Starter, Generator, Cruise Control — 65Windshield Wiper/ Washer System — 9Exterior Lights, Switches — 1Interior Lights, Switches — 7Wiring — 51Refrrigerant R134a Servicing — 134
~3min read

Note For vehicles with an electrically-driven A/C compressor, de-energize the high voltage system before removing the A/C compressor. Refer to → Electrical System Hybrid; Rep. Gr.93.
  • Discharge the refrigerant circuit.
  • Remove the A/C compressor.
Note If a different A/C compressor is installed with a different refrigerant oil, the refrigerant circuit is to be flushed with refrigerant R134a. Refer to → Chapter „Refrigerant Circuit, Flushing (Cleaning) with Refrigerant R134a“.

Electrically-driven A/C compressor:

If an electrically-driven A/C compressor is being replaced that does not have a mechanical fault (for example, a faulty circuit board), then determine how much refrigerant is in this A/C compressor. Note

This A/C compressor must be flushed to get all the refrigerant oil out.

The A/C compressor is flushed in the flow direction (from the low pressure side input to the high pressure side output) So that as much refrigerant oil as possible is flushed out of the A/C compressor, the A/C compressor must be positioned so that the high pressure side output is as low as possible. If an A/C service station without a flushing program is used, the procedure must be performed manually (evacuate, flush 3 times with at least 2 kg refrigerant each and extract refrigerant again, evacuate).

Quantity: for example 50 cm³

Pour so much refrigerant oil out of the new A/C compressor so that only the amount remains (plus 10 cm 3) that had been flushed out of the old A/C compressor beforehand. If the new original A/C compressor has for example, 200 cm3, then only pour out 140 cm3.
  • Pour old refrigerant oil out of A/C compressor. Handling refrigerant oil.
Note In not enough refrigerant oil can be poured out from the A/C compressor to be installed, flush the new A/C compressor. After flushing, fill the A/C compressor to be installed with as much new refrigerant oil as was flushed from the replaced A/C compressor.

Mechanically Driven A/C Compressor:

  • Remove oil drain plug from A/C compressor.
  • To accelerate drainage of refrigerant oil, rotate compressor e.g. by way of ribbed belt pulley/clutch plate of A/C clutch for example. Does not apply to the electrically-driven A/C compressor.
  • Pour old refrigerant oil out of A/C compressor. Handling refrigerant oil.
  • Remove oil drain plug from original part compressor, pour out refrigerant oil and only add a quantity of fresh refrigerant oil equal to the amount poured out of the malfunctioning compressor.
Note If, for example, 70 cm3 of refrigerant oil has been poured out of the malfunctioning A/C compressor and 220 cm3 out of the original part A/C compressor (a small quantity of refrigerant oil remains in the A/C compressor). Fill the compressor to be installed with 70 cm 3 of refrigerant oil (use can be made of oil poured out of original part compressor). Use different refrigerant oils and quantities for the various compressors. Refer to → Rep. Gr.87. If a greater quantity of refrigerant oil (more than approximately 80 cm3) has been poured out of the malfunctioning compressor, the remaining refrigerant oil can also be added to the evaporator or reservoir/receiver/dryer. Refer to → Rep. Gr.87.
  • Replace the restrictor depending on the vehicle.
  • Assemble, evacuate and charge the refrigerant circuit.

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